Attachment for telephone-receivers.



PATENTED FEB. 12, 1907.

J. R. OHALL ATTAGHMENT FOR TELEPH RECEIVERS.

AAAAAAAAAAAAAAAAAAA 12,1906.

UNITED s'rii rns PATENT OFFICE.

JAMES CHALLEN, OF COLLEGEVILLE, PENNSYLVANIA.-

ATTACHMENT FOR TELEPHONE RECEWERS Specification of Letters Patent.

Patented Feb. 12, 1907.

Application filed May 12, 1906. Serial N01 3l6, i81.-

To all whont it may concern:

Be it known that I, JAMES R. CHALLEN, a citizen of the United States, residing in C01- legeville, Pennsylvania, have invented certain Improvements in Attachments for Tele phone-Receivers, of which the following is a specification.

The object of my invention is to provide a telephone-receiver with a simple, cheap, and

eflicient attachment which will serve to ex-' clude local sounds from the ear and will be free from any tendency to cause injury to the delicate organs of the middle and inner ear. This object I attain in the manner hereinafter set forth, reference being had to the accompanying drawings, in which Figure 1 is a perspective view of one form of telephonereceiver with attachment in accordance with my invention. Fig. 2 is a transverse section of the same, on an enlarged scale. Fig. 3 is a view of a retainingring constituting one of the elements of my attachment. Fig. 4 is a view similar to Fig. 2, but illustrating a modification of the invention; and Fig. 5 is a sectional view of the receiver-cap, illustrating still another modification.

Aurists generally recognize the extreme dangerof introducing foreign substances into the middle andinner ear, because the .delicate. organs therein contained are very susceptible to injury from such cause, and for this reason the provision of a telephone receiver with anything in the nature of a tubular projection of relatively small diameter is to be avoided. In carrying out my invention, therefore, I provide the receiver with a centrallydisposed and centrallyapertured dome, of soft rubber or other elastic material,'whose convex face projlects beyond the face of the receiver and 1s t erefore adapted to enter the outer ear and because of its elasticity and flexibility to conform to the contour of said outer ear so closely as to practically exclude local sonnds which would interfere withthe properflow of the soundwaves from the vibrating diaphragm of the telephone-receiver to the tympanum of the car, this result being attained without projection of any element of the attachment from the outer into the middle'ear, and therefore without risk of injury such as would be caused thereby.

. In the drawings, 1 represents the casing of the receiver; 2, the electromagnet the reincontained; 3, the diaphragm, and a the annular cap or face-plate, which is secured to the casing 1 and serves to retain the diaphragm in place thereon. The concavo-convex softrubber dome 5 has a central aperture 6 in its outer portion and is seated at the base upon the face of the cap i, said base having in that construction of the dome which is shown in Fig. 2 an inwardly-projecting flange 7 which is confined against the face of the cap at by means of a metal ring 9, provided on its in ner edge with a series of projecting spurs or barbs 10, which pass through the central opening 11 of the cap 4 and are bent outintegral with the flange, this neck passing through theopening 11 of the cap and l1av ing at its inner end a flange 14', which overlaps the inner face of said cap, the elasticity of the neck 13 permitting the flange to be passed throu h the opening 11 in applying the dome to the cap.

I claim 1. The combination of the receiver-cap, the elastic dome having its. base seated against the outer face of said cap and a ring I engaging said base portion of the dome and having spurs or barbs whereby it is secured to the apertured central portion-of the cap.

2. The combination of the receiver-cap, the elastic dome having an inwardly-projecting base-flange bearing against the outer face of said cap, and means for securing said baseflange to the apertured central portion of the cap.

3. The combination of the receiver-cap,

the elastic dome having an inwardly-projecting base-flange bearing against the outer face of said cap, and a ring bearing on said baseflange and having spurs or barbs whereby it is secured to the apertured central portion of the cap.

In testimony whereof I have signed my JAJNIES R. CHALLEN.

Witnesses:

JOHN B. PATTON, KATE A. BEADLE; 

